The invention relates to a fuel injector for internal combustion engines, or particularly a pump jet having a housing in which an electrical sensor such as an electrical injector needle lift sensor for the injector needle and/or an actuator such as an electromagnetic volume regulator are disposed with electrical connection leads that are brought out of the housing for connection with other leads forming a part of a power supply or control circuit.
In fuel injectors that can be screwed into a cylinder head it has become known through West German Pat. No. A 30 04 424 or European Pat. No. 68 339 to bring the leads of the induction coil of an injector needle lift sensor upwardly through the housing of the injector for engagement with a plug connector. After the injector has been screwed in, a cable with appropriate mating connectors can be plugged into the connectors of the injector. It is considered a disadvantage that such a plug connection is essentially unprotected in the space between the cylinder head and valve cover which is filled with oil and vapors, because the possibility exits, on the one hand, that the contacts may corrode and, on the other hand, there is the considerable danger that, due to engine vibrations, the plug connections may become undone. It is also undesirable, from the point of view of easy maintenance, that, in a 6-cylinder engine, twelve individual connectors must be plugged in. Sealing the penetration of all cables through the valve cover in a fluid-tight manner may also present problems.
In so-called pump jets in which, for example, a high-pressure pump actuated by a cam and a fuel injector are combined into a single unit, the quantity of fuel to be injected can be adjusted with a volume regulator. Here, electromagnetic volume regulators on each pump jet have become known which are controlled by a central processor to permit individual fuel metering for each cylinder.
Pump jets with a flange for clamping the pump jet down on the cylinder head are disclosed, for example, in Austrian Pat. No. 353 558 and Austrian Pat. No. 372 502. However, these jets are neither equipped with an injector needle lift sensor nor with an electromechanical volume regulator.
The object of the invention is the provision of a fuel injector of the kind mentioned in the introduction, in which a simple easy-to-maintain, yet reliable, arrangement for contacting and making electrical connection with the connection leads is possible despite the difficult ambient conditions.
This object can be achieved with the fuel injector disclosed herein which provides, a reliable electrical connection of the jet unit that can be quickly or automatically established with cables leading to a central processor or the like.
Further advantages of the invention and modifications will be apparent from the ensuing description of specific embodiments and the claims appended hereto.